It depends mostly on the material of the core; do you know what it is? If you have a signal generator and scope, you can figure it out by resonating the coil with a known capacitor. I have a 1/4% cap that I use for that purpose.
It is used in the 540 series of Tektronix scopes for the time base. I don't know what they are using now, but it is probably just as accurate. BTW, it is not +-1/4 % but just +1/4%.
Hmm, could I measure inductance with my old tube oscilloscope? (Just alittle math required in reading the dials ) Note that unfortunately, my scope lacks a grid pattern on the display. Instead of an oscillator, could I hook the resistor/inductor pair to the scope's 6V 60 Cycle test lead?
You can also do it with a variable resistor (pot) and a transformer. The trick is to play with the resistor untill you have 1/2 of Vin on the inductor leads.